Solutions For Bridging And Pressure Concentration Reduction At Wound Sites

ABSTRACT

Disclosed herein are devices, systems and methods for delivering reduced pressure to a load-bearing wound site. The device can include a distal port configured to connect to a wound dressing positioned over the wound site; a proximal port located a distance from the distal port and configured to connect to a reduced pressure source, and a conduit body having an inner channel extending between the distal port and the proximal port. When the distal port is applied to the wound dressing positioned over the wound site the proximal port is positioned at a non-load bearing location remote from the wound dressing. The inner channel has a non-circular profile having a width larger than a height of the conduit body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/597,712, filed May 17, 2017, which is a divisional of U.S. patentapplication Ser. No. 13/490,844, filed Jun. 7, 2012, now U.S. Pat. No.9,681,993, which claims benefit under 35 U.S.C. § 119(e) to U.S.Provisional Application Ser. No. 61/494,367, filed on Jun. 7, 2011, allof which are hereby incorporated by reference in their entirety.

BACKGROUND

Pressure sores or decubitus ulcers classically result from localizedtissue ischemia at pressure points on a patient's skin associated withimmobility. However, friction and maceration at the skin site may alsobe contributing factors. Common locations of decubitus ulcers includethe heel, the ankle, the sacral region, the coccygeal region, theischial region, the knee, and the elbow. Traditional therapy forpressure ulcers has focused on prevention of these ulcers, due to thedifficulty of treating the ulcers once they have formed. Thesetreatments include nursing protocols to frequently turn or change theposition of bedbound patients, as well as equipment to redistributefocal forces acting on a patient's skin, such as foam boots andfluidized beds.

Recently, the delivery of reduced pressure wound therapy (RPWT) hasshown promise in the treatment of wounds. Typically, RPWT involvescreating an enclosed space around a wound and connecting this enclosedspace to a reduced pressure source. The creation of the enclosed spaceis achieved most commonly with an adhesive-coated thin polyurethanefilm. A conduit, typically a port that may be connected to flexibletubing, from the enclosure created by the adhesive barrier usually isused to connect to the reduced pressure source which facilitates reducedpressure application to the wound site as well as removal of woundexudates. RPWT has been shown to accelerate or promote the healing of avariety of chronic wounds, including diabetic ulcers, venous stasisulcers, surgical wounds and traumatic wounds.

SUMMARY

Disclosed herein are devices and methods that can be used to providesubstantially airtight seal for reduced pressure wound therapy (RPWT) ornegative pressure therapy (NPT) that can be configured to alsoaccommodate the anatomic particularities of various regions typicallyprone to pressure point ulceration. The devices described herein may below profile and comprise low durometer materials and can be used tobridge a pressure-prone region of the body to another region, so thatany tubing and/or ports which may concentrate pressure transmission atload-bearing surfaces may be positioned remotely from the treatmentsite. In a first embodiment, a low-profile device for delivering reducedpressure to a load-bearing wound site is provided. The device mayinclude a distal port configured to connect to a wound dressingpositioned over the wound site; a proximal port located a distance fromthe distal port and configured to connect to a reduced pressure source,and a conduit body having an inner channel extending between the distalport and the proximal port. When the distal port is applied to the wounddressing positioned over the wound site the proximal port is positionedat a non-load bearing location remote from the wound dressing. The innerchannel may comprise a non-circular profile having a width larger than aheight of the conduit body, which may redistribute any transmittedforces across a larger surface area compared to a circular profile,thereby reducing concentrated regions of applied pressure to underlyingtissue.

The device may further include a sealing layer having an adhesive lowersurface configured to be adhered to the load-bearing wound site. Theadhesive lower surface can include a material that absorbs moisture andmaintains skin health. The conduit body can include an adhesive lowersurface that prevents movement of the conduit body relative to anunderlying skin surface. A junction between the adhesive lower surfaceof the conduit body and the adhesive lower surface of the sealing layercan include an interruption to prevent peel propagation of the conduitbody to the sealing layer. A distal region of the conduit bodysurrounding the distal port can be coupled to an upper surface of thesealing layer. The distal region of the conduit body can be permanentlycoupled to the upper surface. The conduit body can include one or moresupport structures protruding into the channel.

The one or more support structures can mitigate collapse of the channelupon application of external pressure to the conduit body. The one ormore support structures can include elongate ribs or protrusions coupledto an inner wall of the conduit body, and/or grooves or indentations inthe inner wall. The conduit body can have a multi-layer constructionhaving the one or more support structures sandwiched between an uppercover and a lower base. The one or more support structures can have aporosity sufficient to allow the delivery of reduced pressure to thewound site and the flow of fluid from the wound site through the innerchannel. The support structure can be selected from the group consistingof a mesh structure, a synthetic textile, foam, fabric, non-wovenfabric, silicone, urethane, cotton and gauze. The conduit body can havea first durometer and the one or more support structures can have asecond durometer. The first durometer can be less than the seconddurometer or more than the second durometer. The one or more supportstructures can be arranged adjacent the distal port to evenly distributeloads and maintain patency of the distal port upon application ofexternal pressure to the distal port. The distance of the proximal portfrom the distal port can have a range of about 4 inches to about 12inches. In other variations, the distance between the ports may be fromabout 2 inches to about 18 inches, from about 3 inches to about 24inches, or about 12 inches to about 36 inches. The device can furtherinclude a pressure indicator configured to indicate pressure deliveredlocally to the wound site. The pressure indicator may be located in aport structure of the device. The device may also further include acontact surface positioned under the conduit body, and/or a paddingmaterial located on an exterior surface of the conduit body. The devicemay also further comprise a low-tack adhesive located on at least aportion of the padding material configured to adhere to a patient'sskin; and a release liner releasably adhered to the low-tack adhesive,wherein the release liner comprises a porous or padded materialconfigured to contact the patient's skin.

In another embodiment, a reduced pressure therapy device is provided,comprising a conduit structure comprising an upper surface, a lowersurface, and a passageway therebetween, a support structure located inthe passageway, an inlet opening located in the lower surface, an outletopening located in the supper surface, a port coupled to the uppersurface and in fluid communication with the outlet opening, and a firstporous tissue protection structure attached to the lower surface of theconduit structure. The reduced pressure therapy device may furthercomprise an adhesive structure coupled to at least one of the lowersurface of the conduit structure and the first tissue protectionstructure, and a release liner adhered to the adhesive structure, therelease liner comprising a release surface in contact with the adhesivestructure, and a second porous tissue protection structure on a surfaceopposite of the release surface. The release liner may comprise anextension located beyond an edge of the adhesive structure. The firstporous tissue protection structure may comprise a different materialthan the second porous tissue protection structure. The first poroustissue protection device may comprise a foam. The second porous tissueprotection device may comprise a woven material. The support structuremay comprise a foam. The adhesive structure may be attached to the firstporous tissue protection structure. The conduit structure may furthercomprise a proximal region and a distal region. The inlet opening may belocated about the distal region. The outlet opening may be located aboutthe proximal region. The outlet opening may be located halfway betweenthe proximal region and the distal region. The upper surface and thelower surface may be integrally formed. The upper surface and the lowersurface may form a seam along an outer perimeter of the conduitstructure. The upper surface may comprise a non-planar, vacuum formedpolymeric structure and the lower surface comprises a planar polymericstructure. The reduced pressure therapy device may further comprise adressing attached to the conduit about the inlet opening. An edge of thedressing may be aligned with an edge of the first porous tissueprotection structure. The dressing may not overlap with the first poroustissue protection structure. The first tissue protection structurecomprises a lateral perimeter portion that extends beyond a lateralperimeter of the conduit structure.

In another embodiment, a bridging device is provided, comprising a flatconduit with a passageway containing a foam structure, a port adhered toa proximal, upper surface of the flat conduit and in fluid communicationwith the passageway of the flat conduit, a dressing attached to adistal, lower surface of the flat conduit and in fluid communicationwith the passageway of the flat conduit, and a foam pad attached to amiddle and a proximal lower surface of the flat conduit, the foam padcomprising a distal end and an enlarged proximal end, wherein theproximal end comprises a greater width than the distal end. The bridgingdevice may further comprise an adhesive attached to the enlargedproximal end of the foam pad, and a release liner releasably adhered tothe adhesive, the release liner comprising a tab extending beyond aperimeter of the adhesive, a fiber material, and a coating on the fibermaterial that may be releasably adhered to the adhesive. The bridgingmay further comprise a first end of a tubing coupled to the port, andmay further comprise a suction source coupling device attached to asecond end of the tubing.

In another embodiment, a method for treating a patient is provided,comprising orienting a dressing with a pre-attached bridging conduitabout a tissue treatment site, applying the dressing to a tissuetreatment site, and positioning a first skin protection structureattached to an external surface of the bridging conduit in contact witha patient without adhering the first skin protection structure to thepatient, wherein a second porous skin protection structure may bereleasably preattached to the bridging device. The method of claim mayfurther comprise pulling a porous second skin protection structurepreattached to the bridging device, to expose an adhesive, and applyingthe adhesive to the patient to secure the bridging device to thepatient. The method may further comprise attaching a lower surfaceopening of a second bridging conduit to an upper surface opening of thepre-attached bridging conduit.

In another embodiment, a tissue treatment device is provided, comprisingan elongate body with an enlarged proximal end and a distal end smallerthan the proximal end, and a cavity therebetween, an elongate supportstructure located in the cavity and configured to facilitatetransmission of reduced pressure along the elongate body, a tubingconnector attached to the enlarged proximal end of the elongate body andin communication with a proximal opening of the elongate body, and awound cover attached to the distal end of the elongate body and incommunication with a distal opening of the elongate body, the woundcover comprising a non-rectangular, non-square, non-circular, non-ovalshape. The distal opening of the elongate body may have a surface are ofat least 1 square cm and through which at least 1 square cm surface areaof the elongate support structure is exposed. The wound cover may have abi-lobed configuration. The wound cover may comprise an open proximalend and a closed distal end. The wound cover may further comprise a tabextending proximally from an edge of the open proximal end. The woundcover may further comprise cavity with a longitudinal axis between theopen proximal end and the closed distal end, the cavity comprising adiameter transverse to the longitudinal axis that is less than 4 cm. Thediameter transverse to the longitudinal axis may be less than 3 cm or2.5 cm. The elongate support structure comprises a open-cell foam. Theelongate support structure may protrude through the distal opening.

In another embodiment, a method of tissue treatment is provided,comprising attaching at least one wound cover to a treatment site,wherein a foam-based conduit with a tubing connector may be pre-coupledto the at least one wound cover, externally compressing the foam-basedconduit, attaching a vacuum source to the foam-based conduit, andactivating the vacuum source after externally compressing the foam-basedconduit. The method may further comprise maintaining at least someexternal compression of the foam-based conduit while activating thevacuum source.

Other features and advantages should be apparent from the followingdescription of various embodiments, which illustrate, by way of example,the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention are set forth with particularity in theappended claims. A better understanding of the features and advantagesof the present invention will be obtained by reference to the followingdetailed description that sets forth illustrative embodiments, in whichthe principles of the invention are utilized, and the accompanyingdrawings of which:

FIG. 1 shows a perspective view of an embodiment of the device for usewith a negative pressure dressing system;

FIGS. 2A and 2B show side and top cut-away views, respectively, of anembodiment of the device;

FIG. 3 shows a top, cut-away view of another embodiment of the device;

FIG. 4 shows a cross-sectional view of the conduit portion of the devicefrom FIG. 1;

FIG. 5 shows an exploded view of an embodiment of the device;

FIG. 6 shows a close-up of the exploded view of the device of FIG. 5;

FIGS. 7A and 7B show a cross-sectional schematic views of embodiments ofa device;

FIG. 8 shows a bottom view of the device from FIG. 1;

FIG. 9 shows a cut-away side view of a portion of the device;

FIG. 10A is a perspective view and FIG. 10B is an exploded view ofanother embodiment of a device;

FIG. 11A is a perspective view and FIG. 11B is an exploded view ofanother embodiment of a device;

FIG. 12 is a schematic view of an underside of the device of FIGS.11A-11B;

FIG. 13A is a superior perspective view of another bridge device; FIG.13B is an exploded component view of the device in FIG. 13A;

FIG. 13C is a superior perspective view of a variation of the bridgedevice in FIG. 13A with a tubing connector on a side surface of theproximal end;

FIG. 13D is an inferior perspective view of the bridge device of FIG.13A attached to a port, tubing and tubing connector;

FIGS. 13E to 13J depict various exemplary relative configurationsbetween a wound cover and a bridge section.

FIG. 14A and 14B are superior and inferior perspectives of anothervariant of a bridge attached to a port, tubing and tubing connector;

FIGS. 15A is an exploded component view of another variant of a bridgedevice: FIGS. 15B and 15C are superior and inferior perspectives of thebridge device of FIG. 15A attached to a port, tubing and tubingconnector;

FIGS. 16A and 16B are superior perspective and inferior views of stillanother variant of a bridge device configured for use on a digit;

FIGS. 17A and 17B are perspective superior and inferior views of anothervariant of a digit device;

FIG. 18 is a superior perspective view of a branching device; and

FIG. 19 is a superior elevational view of another variation of abranching device.

DETAILED DESCRIPTION

Diabetic patients also often experience chronic ulcers of the lowerextremity. Often, these ulcers are located on the plantar region of thefoot, typically near the heel or metatarsal head. Some anatomicalregions have contours or geometries that make application of a dressingsomewhat challenging, especially in the case of RPWT where a sealbetween the skin and dressing is used to generate therapeutic vacuum atthe wound site. Some anatomical regions such as the sacrum and theplantar region of the foot are subject to certain contact forces on thedressing and/or wound surface such that the dressing itself can worsenthe condition of the wound being treated or cause damage to neighboringtissues. In some cases, the contact forces are unavoidable and in othersare due to patient non-compliance or in the case of neuropathy a patientmay be unaware that they are loading their wound location.

In the case of RPWT, components of the device can contribute to limitingor preventing wound healing, creating additional wounds or evenworsening the condition of the wound being treated. Furthermore,maintenance of a sufficiently airtight seal between a dressing and ananatomical region subject to contact forces may be compromised reducingthe ability of the dressing to draw exudates away from the wound. Forexample, mechanical deformation caused by patient movement, accumulationof moisture (e.g., sweat or interstitial fluid), and by the reducedpressure itself can each affect the seal of the dressing and ability ofthe dressing to draw away fluid.

However, by providing a bridging conduit as described herein, betweenthe wound dressing and the vacuum source, some components of a reducedpressure wound treatment device, such as a port connector that wouldotherwise protrude from the outer surface of a wound dressing, the portconnector may be moved to a location remote to the wound dressing, wherethe mechanical consequences of the port connector may be lessconcerning.

The devices and systems described herein can deliver negative pressureto a wound and reduce pressure points in various anatomic regions,including but not limited to the sacral region, foot (including theheel, plantar surface and dorsal surface), elbow, digits (includingfingers and toes), amputation stumps, skin flaps, skin grafts and othercontoured body parts, and maintain an adequately airtight seal in anyposition (e.g., sitting, standing, lying, etc.) or movement (e.g.,walking, rolling, bending, etc.). The devices and systems describedherein have a low profile and low peak pressure interface with thesealing layer and can reduce the potential for additional tissue damageor healing impairment from excessive pressure applied to the wound siteor surrounding tissues. The devices herein may also reduce shear forcesacting at the dressing-skin interface, which may cause separation orlifting of the dressing, thereby compromising the seal interface andtherapeutic negative pressure delivery.

The device is described herein in the context of the tissue being skin,although it should be appreciated that the device can be used withbiological tissue other than skin. Further, it should be appreciatedthat the devices described herein can be used with a variety of wounddressings used to deliver negative or reduced pressure. Generally, useof the terms “reduced” or “negative” pressure refers to a pressure thatis less than the ambient pressure at a particular tissue site that isbeing subjected to the treatment. The magnitude of the pressurereduction may be characterized as a negative value relative to ambientpressure (e.g. −50 mm Hg, −75 mm Hg, −100 mm Hg and −125 mm Hg), or thedegree of the pressure reduction may be characterized by the absolutepressure level (e.g. a pressure level between an absolute vacuum of 0 mmHg and 760 mm Hg atmospheric pressure). Use of the term “wound” shouldnot be limited to any particular type of injury, discontinuity ordisorder of the skin and underlying tissue layers. The wound can includea chronic open wound such as a diabetic foot ulcer or decubitus pressuresores, venous stasis ulcers, or traumatic or surgical wounds orincisions that are open like burn injuries or have been closed withsutures, staples, adhesives and the like.

Now with respect to FIG. 1, the device 100 may include a flexible,low-profile, conduit body 105, one or more adhesive tabs 110, a distalport 115, and a proximal port 125. The distal port 115 may connect to awound dressing positioned at a wound site. The proximal port 125 canconnect, for example via tubing 130, to any of a variety of negativepressure sources (not shown). The device 100 may be configured to createand maintain a fluidic pathway or channel for the delivery of negativepressure to and removal of exudates from the wound site while preventingcollapse of the system when external forces are applied. The device 100may perform these functions while avoiding or reducing furtherexacerbation of a wound site due to pressure points. Also, relativemovement between the conduit body 105 and the underlying skin surface isprevented thereby avoiding rubbing or the creation of new skin traumadue to the device itself.

The wound dressing can vary and can include the devices and dressingsdescribed in co-pending U.S. Pat. Publ. No. 2010/0174250, filed Jan. 7,2010, which is hereby incorporated by reference in its entirety.Similarly, the negative pressure source can vary, including an electricvacuum pump, in-wall suction, or a non-electrically powered suctiondevice. Components and devices that can be used to provide reducedpressure therapy at a wound site have been described in co-pending U.S.Pat. Pub. No. 2010/0137775, filed on Nov. 25, 2009, which is herebyincorporated by reference in its entirety.

The device 100 may be used to bridge between a dressing at a wound siteand a remote location such as a non-wound region of healthy skin or anon-load bearing location. The device 100 can also be used to bridgebetween two or more wound sites. The dimensions of the conduit body 105can vary. The conduit body 105 may have various lengths and the distancebetween the distal port 115 and the proximal port 125 can vary. In oneembodiment, the conduit body 105 is in the range of about 16 inches toabout 26 inches or more, or more particularly about 18 inches to about24 inches, such as for use with a sacral wound. In another embodiment,the conduit body 105 may have a length in the range of about 2 inches,about 4 inches, about 5 inches, about 7 inches, about 8 inches, about 9inches, about 10 inches, about 11 inches or about 12 inches such as foruse with a foot wound. The conduit body 105 may also have aconfiguration such that the length that can be resized or customized toa length suitable for a particular patient or wound location. Theproximal port 125 may also be configured to be resized or customized toa length suitable for a particular patient or wound location. As anexample, the proximal port 125 may include a connector that can directlyinterface with the reduced pressure source or can connect to tubing 130,which then interfaces with the reduced pressure source. The proximalport 125 may be configured to attach to the conduit body 105 or can beconfigured such that the conduit body 105 may be shortened and theproximal port 125 plugs into or otherwise sealably couples to the open,shortened end. For example, the conduit body 105 may be cut to a desiredlength and accept a barbed connector in the open, cut end. It should beappreciated that the distal port 115 may connect to a location otherthan the wound dressing. For example, the distal port 115 can connect toa proximal port 125 of another device 100 to serially connect multipledevices 100, of the same or different configuration.

As best shown in FIGS. 2A and 2B, a channel 200 can extend through theconduit body 105 from the distal port 115 to the proximal port 125. Itshould be appreciated that more than a single channel 200 can extendthrough the conduit body 105 to the proximal port 125 as shown in FIG.3. Multiple fluidic channels 200 can minimize opportunities for completeocclusion of the conduit body 105 to occur.

FIG. 4 shows a cross-sectional view of the conduit body 105 having acentral channel 200 running through it. The conduit body 105 can have across-section that is generally low profile and non-circular. Thecross-sectional shape of the conduit body 105 in FIG. 4 is oval, but itshould be appreciated that the shape can vary including, but not limitedto, generally flattened, planar, elliptical, rectangular, or othershape, for example to provide the conduit body 105 with the flexibilityto hug a curve of an anatomical structure such as a foot. The geometryof the conduit body 105 can be configured such that the elongated sideof the conduit body 105 is positioned and/or adhered relatively flushwith the skin surface and allows for better deformation of the device100 when external forces are applied to the conduit body 105. Thecross-sectional shape of the conduit body 105 can help to mitigateconduit collapse and also prevent or dissipate pressure points. Theconduit body 105 can have a width to height ratio that can varydepending on where the conduit body 105 is to be located. For example,the conduit body may be between 4 to 6 inches wide for a sacralapplication, whereas the conduit body 105 may be narrower for use withthe foot, such as ½ to 2 inches wide. In some embodiments, the conduitbody 105 may be approximately 1 to 2 inches wide and 1/16 and ¼ inchtall, but it should be appreciated that these dimensions can vary.Generally, the conduit body may comprise a width that is larger than theheight.

The material of the conduit body 105 can vary, including, but notlimited to polyolefins, polypropylene, polyethylene, polyesters,polyethylene terephthalate, polyamides, nylon, silicone, andpolyurethane. Generally, the material of the conduit body 105 can benon-irritating and biocompatible. The materials can be opaque,translucent or transparent. The materials may possess uniform orvariable mechanical properties and geometries to maintain channelpatency while allowing for conformability and flexibility. The materialdurometer may range from 20 to 70 on a Shore A hardness scale andmaterials of different durometers may be combined to achieve desiredoperating characteristics.

The conduit body 105 can also include one or more support structures 205protruding into the channel 200. The support structures 205 prevent ormitigate collapse of the channel 200 upon application of internalvacuum, external pressure to or compression of the conduit body 105,which may provide some residual fluid flow. This may prevent or reducethe risk of interruptions of negative pressure therapy to the wound sitedue to blockage. The support structures 205 may also prevent or reducesignificant pressure concentration during load-bearing.

The configuration of the support structures 205 can vary. For example,FIG. 4 shows the conduit body 105 as a single component having aplurality of support structures 205, such as one or more elongate ribsor other three-dimensional features, coupled to an inner wall of theconduit body 105. The support structures 205 may be integrated togetherwith the walls of the conduit body 105, e.g. the support structure 205and the conduit body 105 may be molded or extruded in an integralfashion. In other examples, however, the support structures 205 need notbe integrated with the walls of the conduit body 105. Instead, theconduit body 105 can have a multi-layer or multi-component constructionas shown in FIGS. 5 and 6, where two or more components may be bondedtogether, for example, by heat welding/radio frequency (RF) weldingprocess, adhesives, or other bonding processes. The support structures205 can be three-dimensional elements that protrude from an uppersurface of a generally planar, middle layer 207 that is sandwichedbetween an upper cover 215 and a lower base 210. The support structures205 of the middle layer 207 can provide support to the upper cover 215such that upon exertion of an external force complete collapse of thechannel 200 is prevented or reduced. The support structures 205 can alsoinclude one or more individual elements positioned within at least aportion of the channel 200 between the cover 215 and base 210 (see FIGS.7A and 7B). The support structures 205 can be positioned within acentral portion of the channel 200, near a side portion of the channel200, or a combination of the two. The support structures 205 can bepunctile structures, elongate ribs, corrugations, or form a criss-crossor egg-crate pattern. The support structures 205 can have a rounded,semi-spherical, square, polygonal, or other cross-sectional shape. Thesupport structure 205 can also include a mesh-like structure such as asynthetic textile structure with sufficient porosity to allow thedelivery of reduced pressure and flow of fluid. The support structure205 may comprise any of a variety of resilient porous structures ormaterials, including but not limited to foam, woven or non-woven spacerfabrics. The support structure 205 can include a fabric or othermaterial having open channels running therethrough. Where the supportstructure comprises a porous material, such as a foam or a fabric-likematerial, the structure may comprise a block or layer-like structure, ormay also comprise the configurations recited above, e.g. corrugations oregg-crate pattern.

In some embodiments, the support structures 205 may be manufactured froma pliable polymeric material such as silicone or urethane or a materialsuch as cotton or gauze or other readily formed material having aconfiguration so as to maintain the flow channel 200 when load-bearingover the conduit body 105. The material can be compliant such that itmaintains its own structure when a force is applied and then removed.The material can, but does not necessarily have memory. Generally, thematerial of the support structures 205 has a low durometer such that itcan allow for greater deformation of the conduit body 105 when externalforces are applied in order to more evenly distribute those forces suchas when a patient with a wound on the plantar surface of the foot walksor a patient with a wound on or near the sacrum lies down. In anembodiment, the durometer of the material is less than 65 Shore A. Inanother embodiment, the material is less than about 50 Shore A, 40 ShoreA, 30 Shore A, or 20 Shore A. The material used for the supportstructure 205 can be the same or different from the material used forthe conduit body 105. In an embodiment, the material used for thesupport structure 205 may be generally stiffer and has a higherdurometer than the material used for the conduit body 105. In anotherembodiment, the material used for the conduit body 105 is generallystiffer and has a higher durometer than the material used for thesupport structure 205. In another embodiment, the material used for theconduit body 105 and the support structure 205 have generally the samestiffness and durometer. In this embodiment, one structure can have ageometric difference that affects a more sturdy aspect to prevent orresist collapse.

A lower surface or “wound side” of the conduit body 105 may providefluid communication between a wound dressing and the channel 200 of theconduit body 105 with the negative pressure source via the distal port115. In an embodiment shown in FIGS. 5 and 6, the lower base 210 and thesupport structure layer 205 can each include distal apertures 220, 225that align to create the distal port 115 of the conduit body 105.Exudate may flow from the wound site through the apertures 220, 225 andinto the channel 200 created between the support structure 205 and theupper cover 215.

As best shown in FIG. 8, the lower surface of the conduit body 105 at ornear the distal port 115 may include or be at least partially covered byan adhesive 145 for connection to a wound dressing. The adhesive 145 cansurround at least a portion of the opening to the distal port 115. Theadhesive 145 may or may not sealably adhere the conduit body and thewound dressing together. In some further variations, a separate oradditional grommet may be provided to couple the conduit body and thewound dressing via their fluid communication openings. It should beappreciated that the distal port 115 can connect to a wound dressingusing other mechanisms such as a static seal or a suction cup seal.

The distal port 115 may be configured to resist closure upon applicationof a load, but is still soft enough to mitigate formation of pressurepoints. The distal port 115 may be used at the wound surface and canhave a construction that disperses pressure points while maintainingfluidic pathways within the port to allow for the delivery of negativepressure and removal of exudates. An interior region of the distal port115 may include one or more supports 150. The supports 150 also mayprevent or resist the channel 200 from collapsing around the opening ofthe distal port 115. FIG. 9 is a cut-away side view of the device nearthe opening of the distal port 115 showing a configuration of supports150 surrounding the opening of the port 115. The supports 150 may bearranged such that the opening of the port 115 is maintained even whenexternal pressure is applied to the port 115. The supports 150 mayevenly distribute loads applied to the distal port 115 and mitigatepressure points by virtue of their generally flat shape with minimalprotrusions. The distal port 115 can have a broad configuration suchthat forces on the distal port 115 tend not to create pressure pointsunderneath. The distal port 115 can have a wide skirt such that when apatient applies a force to the site the pressure is not concentrated ata singular point. The skirt may also be tapered to reduce pressureconcentration at the edges of the distal port 115.

As mentioned above, one or more adhesive tabs 110 can be used to securethe device 100 to the patient's body. The tabs 110 may extend outward onopposite sides of the conduit body 105. Alternatively, each tab 110 mayextend from the conduit body in an alternating or offset fashion on eachside of the device, rather than in pairs as shown in FIG. 5. The device100 may also be secured to the patient's body using a continuous sheetof material as opposed to individual tabs. The tabs 110 may be formed ofa breathable material, such as polyurethane or silicone, that is coatedon a lower, skin-facing surface with a skin-friendly adhesive.Skin-friendly adhesives can include acrylics, hydrocolloids or siliconeadhesives, for example, that may be configured to absorb or transportmoisture from the skin and generally maintain skin health. As best shownin FIGS. 5 and 6, the tabs 110 may include perforations 140 near wherethe tabs 110 extend or protrude outward from the conduit body 105. Theperforations 140 allow for the tabs 110 to be easily removed if deemedunnecessary or undesired for the application of the device 100 to thepatient. The adhesive tabs 110 can be covered by one or more paper orpolymeric backing layers (not shown) such that the device can be securedto a patient's body in an easy and controlled manner.

As noted above, in some embodiments, the support material or structurein the device may comprise a resilient, compressible material such as amesh structure, a synthetic textile, foam, cotton, gauze, and the like.In some variations, while the support material may be generally soft andconformable at atmospheric pressure, when subjected to negativepressure, the material may become substantially compressed and possiblymore rigid or hard. In some variations, for example, a more rigid orhardened foam structure may generate relatively more skin or tissuepressure points or regions, in comparison to the non-evacuated foamstructure. For these and other reasons, it may be beneficial to providea skin protective pad or material on the underside of the deviceconfigured to contact the skin.

The device 100, for example, may also include an underlying contactsurface 135 (see FIGS. 5 and 6) positioned in direct contact with theskin under the device 100. The contact surface 135 can also beintegrated with the device 100. The contact surface 135 may comprise amaterial such as a natural breathable material like cotton gauze tomaintain dryness of the underlying skin and that has natural evaporativeor liquid wicking properties, such as rayon. The contact surface 135 maybe generally thin and can be transparent. Alternatively, the contactsurface 135 can be a compliant material, such as a porous foam or awoven or non-woven textile that is skin-friendly as described above, andthat can provide cushioning for further comfort to a patient wearing thedevice 100. It should be appreciated that the contact surface 135 can bea variety of materials including, but not limited to polymeric materialsuch as polyurethane, elastomeric polyester, or polyethylene, foam,mesh, gauze, sponge, stacked mesh matrix, adhesive, hydrocolloid,hydrogel, acrylic adhesive or other biocompatible material. The contactsurface 135 may be adhesively coated in some embodiments. The adhesivecoating may be located contiguously or non-contiguously along theperimeter or spaced apart regions along the contact surface 135.

Referring back to FIG. 1 the conduit body 105 may have two connectionjunctions 120 along its length such that the conduit body 105 includesthree separate parts that can be joined together during manufacturing.Alternatively, FIGS. 5 and 6 show the conduit body 105 having amulti-layer or multi-component construction. The layers of the conduitbody 105 can be heat bonded, ultrasonic, friction bonded, RF or laserwelded or otherwise adhered together.

One or both of the ports 115, 125 can include a pressure sensitivemechanism or indicator 230 (FIG. 5) that provides information to a userabout the pressure being delivered through the conduit body 105 andlocally to the wound site. The indicator can include those embodimentsdescribed in U.S. Publ. No. 2010/00137775, filed on Nov. 25, 2009, whichis hereby incorporated by reference in its entirety. The indicator 230can provide assurance to a user that the desired reduced pressure levelis delivered to the wound for optimal therapy and the pressure is notoccluded or otherwise not compromised such as by clogging of the fluidcommunication conduit between the reduced pressure source and thedressing on the wound site. The indicator 230 can be positioned in oneor more locations along the device 100 such as within the tubing 130, ona region of the conduit body 105, near the distal port 115 or proximalport 125. In an embodiment, the indicator 230 can be integrated into thebody of the distal and/or proximal ports. The indicator 230 can be aradial section of a compliant material that surrounds a region of theport or forms an exterior wall of the port covering an interior walland/or at least a portion of the wound site. A volume between thecompliant exterior wall and the wound site can be reduced and thecompliant exterior wall deformed upon exposure of the volume to reducedpressure or formation of a pressure gradient upon delivery of reducedpressure to the wound site by a reduced pressure source. The indicator230 can provide an indication of the pressure under the structure andwhether or not the pressure gradient is sufficient or is lost orcompromised. The indicator 230 can provide a visible and/or tactilenotification to a user regarding the pressure gradient.

The exterior wall of the indicator 230 may be translucent, transparentor opaque. In one embodiment, the exterior wall of the indicator 230 istranslucent and obscures a visually distinctive region when the exteriorwall is a distance away from the wound site. When a pressure gradient ispresent the exterior wall of the indicator 230 can approach the woundsite and decrease the distance between the exterior wall and thevisually distinctive region until the visually distinctive region isvisible through the exterior wall. The visually distinctive region caninclude a color, pigment, symbol, pattern, text and the like. In anembodiment the exterior wall of the indicator 230 can be a first colorand an interior wall can be a second color such that contact between theexterior wall and the interior wall provides a visible indication of thepressure gradient due to change in color. Deformation of the exteriorwall of the indicator 230 can result in a change from a first profile toa second profile. In an embodiment, the relative position of theexterior wall between the first profile and the second profile can beindicative of an amount of pressure delivered to the wound site. Thechange in profile can also provide a tactile change.

FIGS. 10A and 10B depict another embodiment of a device 1000. The device1000 may include a flexible, low-profile conduit body 1005 extendingfrom a thin, flexible sealing layer 1007 configured to seal over a woundsite. The sealing layer 1007 may have a distal aperture 1115 that alignswith a distal portion of the conduit body 1005 such that reducedpressure can be delivered to the wound site through the conduit body1005. Reduced pressure can be delivered from a reduced pressure source(not shown) through the conduit body 1005, which can include a proximalaperture 1035 configured to couple to a proximal port 1125 and tubing1030 extending from the reduced pressure source.

As shown in FIG. 10B, the sealing layer 1007 may include an elongateextension 1010 defining a skin-side portion of the conduit body 1005.The conduit body 1005 may include an inner spacer 1012 and a top layer1014. The inner spacer 1012 of the conduit body 1005 may be a porousmaterial sealed circumferentially, e.g. by laminating together the edges(or other regions) of the elongate extension 1010 and the top layer1014. The elongate extension 1010 and the top layer 1014 can each bethin sheets of impermeable material. The inner spacer 1012 may also besealed circumferentially by one sheet of impermeable material wrappedaround it and the two free ends sealed. The inner spacer 1012 of theconduit body 1005 can include foam, fabrics, such as spacer fabric, 3-Dknitted or woven fabrics, or one or more molded features as describedabove that allow the conduit body 1005 to stay patent when a negativepressure is applied or external pressure is exerted against the conduitbody 1005.

The sealing layer 1007 can be hydrocolloid or other material such ashydrogel, acrylic, polyurethane, and others. The sealing layer 1007 caninclude a skin-friendly adhesive to obtain a substantially airtight sealof the wound. The same adhesive can coat both the skin-side portion ofthe conduit body 1005 and the sealing layer 1007. The sealing layer 1007can be adhered down to the patient's skin surrounding the wound site.The conduit body 1005 leading from the wound site can also be adhereddown to the patient's skin preventing movement of the conduit body 1005relative to the patient's skin, which can cause shear trauma. Theadhesive can be masked off or otherwise interrupted near the junction ofthe sealing layer 1007 and the conduit body 1005 to stop peelpropagation of the conduit adhesive to the sealing layer and potentiallydisrupt the wound seal. A separate release liner (not shown) can be usedon the conduit body 1005 and the sealing layer 1007 to help with themanipulation of the device 1000 during application.

The sealing layer 1007 may or may not include an elongate extension 1010to which the inner spacer 1012 and top layer 1014 of the conduit body1005 are attached, as described above. The conduit body 1005 can includean inner spacer 1012 sealed circumferentially by a top layer 1014 and alower layer 1016 as shown in FIGS. 11A and 11B. The conduit body 1005can also include an inner spacer 1012 sealed circumferentially by asingle sheet of impermeable material. The lower layer 1016 of theconduit body 1005 can be coupled to an upper surface of the sealinglayer 1007. In an embodiment, a distal aperture 1018 of the lower layer1016 of the conduit body 1005 can be generally aligned with or surroundthe distal aperture 1115 of the sealing layer 1007. The spacer 1012 canpass through the aperture 1018 of the lower layer 1016 such that at thedistal end of the conduit the spacer 1012 is positioned below theconduit body 1005. In this example, the aperture 1115 can align with thespacer 1012, but not necessarily align with the aperture 1018 throughwhich the spacer 1012 passed. The lower layer 1016 of the conduit body1005 can be coupled to the sealing layer 1007 by permanent bonding or bya reversible adhesive.

In an embodiment best shown in FIG. 12, the conduit body 1005 is coupledto the sealing layer 1007 in region 1022 surrounding the distal aperture1115 of the sealing layer 1007. The conduit body 1005 is not coupled tothe sealing layer 1007 in region 1024 near an edge of the sealing layer1007. This creates a flap 1020 on the sealing layer 1007 that remainsfree relative to the conduit body 1005. The flap 1020 can be used tomanipulate the sealing layer 1007 and provides flexibility to the userduring application of the sealing layer 1007. The absence of adhesive onthe conduit body 1005 in region 1024 overlying the flap 1020 (and beyondthe flap 1020 as shown in FIG. 12) can also act as an interruption suchthat peeling of the conduit body 1005 adhesive from the patient's skindoes not propagate to the sealing layer 1007.

As described with previous embodiments, the dimensions of the componentsof the device 1000 can vary and can depend on the location to which thedevice 1000 will be adhered. In some embodiments, the sealing layer 1007can be between about 2 inches by 7 inches, or between about 3 inches byabout 5 inches. The conduit body 1005 can have a length configured sothat the proximal port 1125 can be positioned at a location convenientwhile reducing interference to adjuvant therapies such as offloadingdevices such as an orthotic, walking boot or total contact cast. Forexample, the distal aperture 1115 of the sealing layer 1007 may bepositioned on the dorsum of the foot for treating a plantar surfacewound and the conduit body 1005 may have a length between about 100 mmto about 250 mm such that the proximal port 1125 is positioned in alocation remote from the dorsum of the foot. The conduit body 1005 maybe thin enough such that it doesn't cause or otherwise reduces excesspressure, but may be thick enough such that there is enough free spaceto conduct negative pressure through the conduit body 1005. In someembodiments, the thickness of the conduit body 1005 may be in the rangeof about 1 mm to about inches to about 15 mm, about 2 mm to about 12 mm,about 3 mm to about 10 mm, about 5 mm to about 8 mm, or about 6 mm toabout 7 mm. In some embodiments, the conduit body 1005 is at least about6 mm. The conduit body 1005 may have a width that provides for thepressure to be spread out as much as possible, but not so wide as tomake the device difficult to handle. In some variations, the width ofthe conduit body 1005 may be in the range of about 5 mm to about 50 mm,about 10 mm to about 40 mm, about 20 mm to about 30 mm, or about 25 mmto about 35 mm. The conduit body 1005 can also have a width that variesalong its length. For example, the width of the conduit body 1005 cantaper as it nears the sealing layer 1007. The length of the conduit bodymay be in the range of about 50 mm to about 500 mm, about 120 mm toabout 400 mm, about 150 mm to about 300 mm, about 200 mm to about 300mm, or about 220 mm to about 250 mm. It should be appreciated thatdimensions of the components provided herein are for example and can belonger, shorter, wider, narrower etc. depending on the anatomy to whichthey may be applied.

As noted above, some embodiments described herein may be used for thetreatment of a foot, and in particular, for the treatment of woundslocated on a plantar surface of a foot. In these embodiments, it may bedesirable to utilize negative pressure wound dressings configured toameliorate pressure points on the bottom of the foot that wouldotherwise be exacerbated by traditional negative pressure wounddressings. These pressure points may result from protruding structuresof the wound dressing, e.g. a port connector, and/or may result from therelative rigidity of the materials, regardless of the degree ofprotrusion. In one particular example, at times it may be beneficial tobridge a dressing located on a plantar surface of a foot onto the top(dorsum) of the foot and position any port/tubing transitions at thatarea, where pressure points are less of a concern. Alternatively, it maybe beneficial to bridge the dressing to a point higher on the patient'sleg, such as to the calf. In the former case, where the dressing isbridged to the dorsum of the foot, it may be beneficial in someembodiments to secure the bridge, i.e. by adhesion, to the dorsalsurface, as this may minimize rubbing or other discomfort if the patientis wearing an offloading appliance or other footwear. In the later case,where the dressing is bridged to a higher point on the calf, it may bemore favorable not to adhere the dressing to the patient, as the twopoints of possible adhesion (plantar surface of foot and point onpatient's leg) are separated by a the patient's ankle, which is anarticulation point. Having an interposed joint underlying differentregions of a dressing and bridge may cause occlusion, protrusion,discomfort and/or undesirable stretching of the dressing. Also, in thecase of having the bridge on a point on the patient's leg (as opposed tothe dorsum of the foot), there may be less likelihood that the proximalend of a bridging conduit may be located under a restrictive coveringover (such as a shoe), so in many cases the risk of discomfort of notbeing adhered is less. In other examples, however, a patient may bewearing elastic or pneumatic compression stockings or boots, or haveother reasons where it may be preferable to adhere the bridge to theunderlying tissue or skin. Thus, it may be desirable to configure abridge device with an adhesive that is protected by a release layercomprising a padded or resilient, non-adhesive material that may beoptionally removed if skin adhesion is desired, but which provides apadded or resilient skin contact surface if left intact with theadhesive.

FIGS. 13A and 13B depict another variant of a bridging device 1300,comprising a wound cover 1302, which in turn comprises a substantiallyairtight polymeric layer or material sufficient to maintain a reducedpressure environment, and a hydrocolloid or other adhesive layer (notshown) configured to provide a substantially airtight seal between thepolymeric layer and the skin or tissue surrounding the treatment area.The wound cover 1302 further comprises an opening 1304, over which isplaced a bridge section 1306, such that the interior of the bridgesection 1306 is in fluid communication with the space immediately belowthe opening 1304 in the wound cover 1302. The wound cover 1302 and thebridge section 1306 may be attached in an airtight manner by any of avariety of processes described herein, but in the particular embodimentdepicted in FIG. 13B, a piece of double-sided airtight tape is usedaround the opening 1304. The bridge section 1306 may comprise a unibodytubular structure, or may comprise two or more polyurethane structureswhich are sealably coupled together, e.g. a bottom bridge layer 1308 andtop bridge layer 1310. As disclosed above, the two polyurethane layersmay be sealed together along a perimeter by any means known in the art,e.g. radiofrequency welding or an adhesive, to form an internal cavity.Located in the cavity of the bridge section 1306, a resilient supportstructure 1312, including one or more pieces of open-cell reticulatedfoam, or any other porous material as mentioned previously which canconduct negative pressure. In the particular embodiment depicted inFIGS. 13A and 13B, the bridge section 1306 comprises rounded ends 1314,1316 with a midsection 1318 comprising a uniform width, but in othervariations, the bridge section may comprise other shapes, e.g.frustoconical, ellipsoidal or oval, or otherwise tapered. The dimensionsof the bridge section 1306 and the resilient support structure 1312 maycomprise dimensions and/or materials as described for device 1000 andits conduit body 1005, in addition to other embodiments describedherein, e.g. devices 100, 1400, or conduit body 105.

Although the bridge section 1306 in FIGS. 13A and 13B is configured tobe in fluid communication with a single center opening of the woundcover 1302, in other variations, the bridge section and wound maycomprise an off-center fluid communication opening (e.g. orientedanywhere along an edge of the wound cover and outward, as shown in FIG.13E), and/or the multiple fluid communication openings may be providedbetween the bridge section and wound cover, along the overlapping lengthof the bridge section (e.g. FIG. 13F). The relative orientation of thebridge section with regards to the wound cover in FIGS. 13A and 13B is aradial and orthogonal with regards to the square shape of the woundcover, but in other variations, the bridge section may comprise a radialbut non-orthogonal orientation, e.g. from the center of the wound coverto a corner of the wound cover (FIG. 13G), or comprise an orthogonal butnon-radial orientation, e.g. from the center of one edge to an adjacentcover corner (FIG. 13H), or from one corner to an adjacent corner (FIG.13I). Other orientations are also contemplated, e.g. corner tonon-adjacent corner, as well as non-linear (FIG. 13J). Also, in someembodiments, the bottom layer of the bridge section may be integrallyformed with the wound cover.

In embodiments where the bridge section comprises multiple structuressealed together, components such as the bottom bridge layer and topbridge layer may comprise generally planar sheets, but in some furthervariations, one or more components may comprise non-planarconfigurations when in an unbiased state, other otherwise not subjectedto forces acting upon it. For example, in the embodiment depicted inFIG. 13B, top bridge layer 1310 may be injection molded, or heat orvacuum formed into a non-planar shape, e.g. a recess or open cavityconfigured to receive the resilient support structure 1312. The bottomand top bridge layers may comprise the same or different materials, andthe same or different thickness. Prior to vacuum forming the layers, ifany, the material may comprise a thickness of about 0.1 mm to about 0.2mm, and may comprise polyurethane, polyethylene, or any of a variety ofother polymeric materials. The recess or open cavity may have a depththat slightly larger or smaller than the thickness of the resilientsupport structure 1312. In some variations, the recess is about 0.5 mmto about 2 mm greater than the thickness of the support structure 1312,while in other variations, the recess is about 0.5 mm to about 1.5 mm,about 1 mm to about 2 mm, or about 1.5 mm to about 2 mm larger, forexample. In some variations, the recess or cavity may comprise anabsolute depth of about 4 mm to about 15 mm or more, sometimes about 6mm to about 12 mm, or about 8 mm to about 10 mm. In some variations, useof one or more pre-formed non-planar structures may reduce the deadspace in the cavity that lies between the resilient support structure1312 and the bottom and top bridge layers 1308 and 1310 when the bridgeconduit is at ambient pressure. In embodiments comprising manual vacuumsystems or vacuum systems of limited vacuum capacity, the reduced deadspace may permit such systems to provide a longer duration of use beforereplacement or recharge of the vacuum source, as the lateral dead spacemay collapse anyway upon the application of reduced pressure, andtherefore may not function as part of the effective conduit volume forconveying reduced pressure.

The bottom layer 1308 of the bridge section 1306 may further comprises asoft padding 1322 such as foam, which is not in fluid communication withthe interior of the bridge. When negative pressure is applied to thesystem, the foam in the interior of the bridge will compress and harden;however the foam on the exterior of the bridge which is not in fluidcommunication with the interior will remain soft and pliable, enhancingthe ability of the dressing to reduce pressure points on the patient. Insome variations, the thickness of the padding 1320 may be in the rangeof about 1 mm to about 10 mm, about 1 mm to about 8 mm, about 2 mm toabout 5 mm, about 2 mm to about 4 mm, about 2 mm to about 3 mm.

Typically, but not always, the greatest pressure point of the bridgedevice or bridge section 1306 is where the traditional suction tubingattaches to it. The attachment of the tubing may be configured such thatthe tubing is generally parallel to the plane of the dressing or bridgeand terminate in an elastomeric port structure 1324, as depicted inFIGS. 13A and 13B. This port structure 1324 may be positioned over anopening 1326 in the top layer 1310 of the bridge section 1306 and thenbends the fluid path 90 degrees such that the tubing is in fluidcommunication with the interior of the bridge. In another embodiment,depicted in FIG. 13C, the tubing may run parallel to the plane of thedressing 1302 and bridge section 1306, and terminate directly into aside connector 1328 located in the side surface of the proximal end 1316of the bridge section 1305, where it is welded or otherwise affixed inan airtight manner to the bridge section 1305. In this embodiment, thereis no bend in the fluid path of the connector 1328. Also, in thisparticular embodiment, the base of the connector 1328 is attached to theformed top layer 1310 of the bridge section 1306, but in othervariations, the base of the connector may attached to both layers 1308,1310.

As shown in FIG. 13B, in some further variations, an adhesive 1330, suchas a low-tack non-traumatic silicone, hydrocolloid or acrylic layer, maybe provided on the bottom of the padding 1322, along with a releaseliner 1332. In some variations, the release liner 1332 may be a typicalrelease liner that is generally configured to protect the adhesive untilready for use or to provide some rigidity to the underlying structure,and may comprise a protruding flap or tab 1334 to facilitate removal. Insome variations, the flap or tab 1334 may be smaller or larger (e.g. thesame width as the rest of the release liner 1332) than what is depictedin FIG. 13B, and may be optionally pre-folded over itself. Although theembodiment depicted in FIG. 13B depicts a tab 1334 as located at thedistal end 1314 of the bridge section 1306, in other variations, the tabmay be located at the proximal end 1316 or between the ends 1314, 1316.FIG. 13D depicts the fully constructed device 1300, along with a tubing1336, check valve 1338 and tubing connector 1340 attached to the device1300.

In other variations, however, the release liner 1332, in contrast totypical liners, may comprise a skin-friendly surface or material which,at the clinician's election, may either be removed to expose theadhesive, or left in place to allow the bridge to move relative to thepatient's skin. The substrate or material may comprise a soft, resilientmaterials, such as felt or other woven or non-woven fibrous materialsmade from polypropylene, rayon, polyethylene terephthalate or acrylicfibers, for example. The material may be a hydrophobic absorbentmaterial or a wicking material that facilitates moisture evaporation viacapillary action. The material may possess moisture transport ratesgreater than about 200 g/m²/day, about 400 g/m²/day, about 1000 g/m²/dayor higher.

Referring still to the embodiment depicted in FIG. 13B, the padding 1322(and optional adhesive 1330 and 1332) may comprise dimensions that areat or within the peripheral boundary or edge of the bridge section 1306.In other embodiments, however, such as the device 1400 depicted in FIGS.14A and 14B, the device 1400 may be similar to device 1300 inconstruction and in described variations, but also includes a pad 1402(and optional adhesive and release liner 1404) that comprises dimensionsthat are larger than the bridge section 1406 in at least one region ordimension. In this particular embodiment, the pad/release liner 1402,1404 comprises a bulbous or otherwise enlarged proximal end 1406. Insome variations, the increased surface area of the pad and release liner1402, 1404 may provide greater surface protection (if usednon-adhesively) or greater adhesion (if used adhesively) at the proximalend 1410 of the bridge section 1406, which may be prone displacementpatient movement transmitted through loose tubing 1414, or because ithas a relatively smaller surface area than the wound covering 1412.Release liner 1404 may otherwise have any of a variety of configurationsas described for release liner 1322 of device 1300. The device 1400 inFIGS. 14A and 14B is also depicted with attached tubing 1414, as well asa check valve 1416 and tubing connector 1418 configured to form aninterfit with a vacuum source (not shown). The tubing 1414, check valve1416 and/or tubing connector 1418 may be attached to the device 1400 atthe point of use, or at the point of manufacture. In some variations, apre-attached tubing connector 1418 may be easier to attach to a vacuumsource compared to the act of manually attempting to pass a tubing endover a multi-flanged connector in a manner that provides an airtightseal. The particular connector 1418 depicted herein is a latch-basedquick-release connector configured for use with the suction cartridgedisclosed in U.S. Pat. No. 8,128,607, which is hereby incorporated byreference in its entirety, but one of skill in the art that any of avariety of connector configurations may be used, e.g. Luer fitting, JohnGuest quick connector, collet connector, etc. or a customized fitting.

In some other variations of the bridge device, such as the device 1500depicted in FIGS. 15A to 15C, the device 1500 may be similar to devices1300 and 1400 in materials, construction and in described variations,but the adhesive layer 1502 (and release liner 1504) of the bridgesection 1506 may comprise a region or surface area that is less than theentire area of the pad 1508. In the depicted example, the adhesive layer1502 is generally limited to the proximal end, or enlarged region 150,or the pad 1506, but one of skill in the art will understand that thelocation and/or size may be varied along the length of the pad, and thatmultiple separate or contiguous may be provided, each with independentrelease liners to provide selective use of the provided adhesive regionsif any. Release liner 1504 may otherwise have any of a variety ofconfigurations as described for release liner 1322 of device 1300, orliner 1406 of device 1400. The device 1500 in FIGS. 15B and 15C is alsodepicted with attached wound cover 1512, tubing 1514, as well as a checkvalve 1516 and tubing connector 1518 configured to form an interfit witha vacuum source (not shown).

In some variations, the pad may be attached at the point of use, or maybe otherwise supplied as a separate product ready for attachment at thepoint of manufacture. As shown in FIG. 15A, for example, the pad 1506may be provided with an upper adhesive layer 1520 that is configured forattachment to an undersurface of a bridging product, e.g. bridge section1506 of device 1500. Because the bridge section 1506 of device 1500 isnarrower at its proximal end than the pad 1506, the adhesive layer 1520need comprise an enlarged proximal end. This upper adhesive layer 1520may also be provided with its own upper release layer 1522, to protectthe adhesive layer 1520 until ready for attachment. However, upperrelease layer 1522 need not comprise any skin-protectivecharacteristics, as described for release liners 1322, 1406 and 1506. Insome variations, as shown in FIG. 15A, one or more tie layers 1524 maybe provided to facilitate adhesion of the skin adhesive layer 1502 tothe pad 1506. In the depicted sample, the tie layer may comprise anadhesive such as acrylic, while the skin adhesive layer 1502 maycomprise a low-tack adhesive as described elsewhere. This tie layer isnot limited to the smaller adhesive layer embodiment of device 1500, andmay also be provided for the adhesive layers of device 1300 and 1400, aswell as other embodiments described herein.

Although the embodiments depicted in FIGS. 13A to 15C include deviceswith bridge sections that have either a generally uniform width alongtheir length, or a generally uniform width in the middle and distally,but with an enlarged proximal end, in other variations, the bridgingsection may generally taper along its length. Such dressings may bebeneficial when treating tissue located on toes or fingers. In othervariations, however, smaller, uniform width conduits may also providedfor use on toes or fingers. The wound cover may also be configured foruse on the fingers or toes, which may include a smaller size as well asa different shape that is better suited for wrapping around a digit, orat the end of a digit.

For example, for a regular bridge dressing, the base layer may havedimensions of about 14 cm by about 11 cm, and the bridge may be about 22cm long and about 2.5 cm wide. In contrast, the dressing 1600 depictedin FIGS. 16A and 16B is tailored to, but not limited to, use in the toe,whereby the wound cover 1602 may have reduced dimensions, e.g. 8 cm×5cm, while the bridge section 1604 may also be smaller, e.g. about 15 cmlong and about 1.5 cm wide. The wound cover 1602 in this embodiment maybe shaped to facilitate forming seals around highly curved surfaces,such as having re-curved edges or “butterfly” lobes 1604 on one or twoopposing ends of the wound cover 1602. The bridge section 1606 and woundcover 1602 may otherwise comprise similar materials and construction asdescribed elsewhere herein, including the adhesive and release layersdescribed for devices 1300, 1400, 1500 and others herein.

In some variations, due to surface area constraints of a digit, theremay not be sufficient space to provide an intervening contact layer ormaterial, e.g. gauze or foam, between the wound cover and the treatedtissue. In such instances, the digit treatment device may comprise adistal opening 1608 between the bridge section 1606 and the wound cover1602 that is sufficiently large so that the conduit material 1610 issufficiently exposed and may function as the contact layer. In somefurther variations, the conduit material 1610 may protrude from thedistal opening 1608 or otherwise lie below the wound cover 1602, whichmay further facilitate tissue contact. In some further variations, thedistal end of the conduit material 1610 may be larger than the distalopening 1608 of the wound cover 1602. This larger size may facilitateplacement of the device 1600 by allowing the device 1600 to be placedsuch that the distal opening 1608 of the wound cover 1602 does not needto lie directly over the wound. The clinician may thus place the distalopening 1608 of the wound cover 1602 at a point away from the wound, aslong as the conduit material 1610 that lies underneath the wound cover1602 is oriented such that it touches the wound. In this manner, thedistal opening 1608 of the wound cover 1602 may be placed in aconvenient location, such as the top of the big toe, and the conduitmaterial 1610 under the wound cover 1602 may be extended to reach awound in a less convenient location, such as the tip of the toe. In someembodiments, the bottom surface of the wound cover 1602 may comprise asheet material which will protect the skin underneath the conduit frommoisture that would accumulate due to the presence of the conduitsection, e.g. rayon or other non-adherent wicking layer.

In some further variations, the wound cover may be further shaped suchthat it has three-dimensional structure, instead of being substantiallyplanar. Such base layer shapes may include domes, paraboloids or closedcylinders, for example. In some variations, a three-dimensional shapemay be provided with the adhesive (hydrocolloid or other) is present onthe concave surface of the shape. As a more concave shape (i.e. the baselayer) is conformed to an even more convex shape, of a digit orequivalently less concave shape (i.e. the body), the more concave shapemay be configured with a structure and/or a material that stretches outin order to assume the same contours as the less or more concave shape.This stretching may mitigate wrinkling of the wound cover which mightlead to leak paths. In the device 1700 depicted in FIGS. 17A and 17B,for example, the wound cover 1702 comprises a substantially cylindricalcavity 1704 with a proximal opening 1706 and a closed distal end 1708,which is configured for receiving a finger or toe. A proximal flap orlobe 1710, which may or may not be contiguous with the edge of theproximal opening 1706, may be provided. This proximal flap or lobe 1710may provide additional surface area to secure the bridge section 1712 tothe wound cover 1702 during manufacturing, and/or to provide additionalmaterial to wrap around and secure the device 1700 to the digit. Thebridge section 1712 and wound cover 1702 may otherwise comprise similarmaterials and construction as described elsewhere herein, including theadhesive and release layers described for devices 1300, 1400, 1500, 1600and others herein.

Although the bridging devices described above are configured to providea bridge between a treatment site and a more described tubing attachmentlocation, in other embodiments, the bridge device may be configured toprovide a bridge between multiple treatment sites and one or more vacuumsources. The device 1800 illustrated in FIG. 18, is an example of amulti-site treatment device with multiple wound covers 1802, each influid communication with a hub 1804 via secondary conduit segments 1806.Although each of the depicted wound covers 1802 is identical in size,shape and angular spacing, in other variations, one or more of the woundcovers may comprise a different size, shape or spacing. Also, thesecondary conduit segments 1806 are depicted as having the same generalconfiguration, size and shape, but in other variations, one or more ofthe conduit segments may comprise a different size or shape.Furthermore, the conduit segments 1806 are depicted as converging to acommon location of the hub 1804, but in other variations, the conduitsegments 1806 may attach to different locations along the hub 1804. Thisparticular embodiment also depicts a primary conduit segment 1808proximal to the hub 1804, to which a tubing connector 1810 is attachedand spaced away from most proximal branch of a secondary conduitsegments 1806. In other embodiments, however, the tubing connector maybe at the intersection of the most proximal secondary conduit segments1806, or even distal to the most proximal secondary conduit segments1806. For example, FIG. 19 depicts one variation of a device 1900comprising two wound covers 1902 located 180 degrees apart andequidistant from a hub 1904 and tubing connector 1906. In othervariations, the covers 1902 may be located at a different separationangle, e.g. about 15 degrees apart, about 30 degrees apart, about 45degrees apart, about 60 degrees apart, about 75 degrees apart, about 90degrees apart, about 105 degrees apart, about 120 degrees apart, about135 degrees apart, about 150 degrees apart, or about 165 degrees apart.This particular hub 1904 also comprises an enlarged pad 1908 with atabbed release liner 1910, but in other variations, the pad may notextend from the edges of the conduit 1912. Also, in other examples, thetubing connector 1906 may be located closer to one of the wound covers1902. Furthermore, although this particular example depicts threesecondary conduit segments 1806, in other variations, there may be two,three, four or any number of such bridge conduits emanating from thecentral hub. Alternatively, the structural arrangement could be morebranched, such that there is a single bridge conduit that splits intomultiple conduits at some point along its length. Except as above, thematerials, constructions and variations of the above embodiment may bethe same as described for other embodiments, herein, including but notlimited to devices 1300, 1400, 1500, 1600, 1700 and others herein.Asdepicted in FIG. 18, at least the branch point of two units areequidistant from the two wounds that they are treating; however in caseswhere this is difficult to achieve, the branch that is too long may be“z-folded” against itself to reduce its effective length. In still othervariations, the devices may comprise accordion-like regions which maylength and/or angle adjustment of one or more of the secondary conduitsegments 1806.

One potential benefit of the branching conduit device is that theypermit the treatment of multiple regions without the need for rigidcomponents, such as Y-connectors and affords all of the advantages ofbridging. If any number of the plurality of the individual conduits isnot to be used, it is possible to cut it from the hub or the branchedstructure and seal the end to prevent or resist vacuum leakage. The cutbranch may be sealed using clips, clamps and/or adhesive sheets oradhesives coatings.

In some procedures where the above embodiments and variations areemployed, to reduce waste and/or prolong treatment duration beforeexchanging or otherwise replenishing the vacuum source, the user mayexternally compress the devices to evacuate as much residual air in thedevice, before attaching a vacuum source.

It should be appreciated that one or more of the components of any ofthe systems and devices described herein can include an additive(s) suchas antimicrobials, anti-bacterials, antibiotics, antivirals,antifungals, antiseptics, anti-inflammatories, anesthetics and othertherapies. One or more of the components of the system can also includeanti-clotting materials to help mitigate issues with blockage within thelong conduit structures.

While a number of embodiments have been shown and described herein, oneof skill in the art will understand that these embodiments are providedby way of example only. Numerous variations, changes, and substitutionsmay be made those skilled in the art without departing from theinvention. It should be understood that various alternatives to theembodiments described herein may also be employed. It is intended thatthe following claims define the scope of the invention and that methodsand structures within the scope of these claims and their equivalents becovered thereby. For all of the embodiments described herein, the stepsof the methods need not be performed sequentially.

What is claimed is:
 1. A bridging device, comprising: a flat conduit with a passageway containing a foam structure; a port adhered to a proximal, upper surface of the flat conduit and in fluid communication with the passageway of the flat conduit; a dressing attached to a distal, lower surface of the flat conduit and in fluid communication with the passageway of the flat conduit; and a foam pad attached to a middle and a proximal lower surface of the flat conduit, the foam pad comprising a distal end and an enlarged proximal end, wherein the proximal end comprises a greater width than the distal end.
 2. The bridging device of claim 1, further comprising: an adhesive attached to the enlarged proximal end of the foam pad; and a release liner releasably adhered to the adhesive, the release liner comprising a tab extending beyond a perimeter of the adhesive; a fiber material, and a coating on the fiber material that is releasably adhered to the adhesive.
 3. The bridging device of claim 1, further comprising a first end of a tubing coupled to the port.
 4. The bridging device of claim 3, further comprising a suction source coupling device attached to a second end of the tubing.
 5. A method for treating a patient using a bridging device, comprising: orienting a dressing with a pre-attached bridging conduit about a tissue treatment site; applying the dressing to a tissue treatment site; and positioning a first skin protection structure attached to an external surface of the bridging conduit in contact with a patient without adhering the first skin protection structure to the patient, wherein a second porous skin protection structure is releasably pre-attached to the bridging device.
 6. The method of claim 5, further comprising: pulling a porous second skin protection structure pre-attached to the bridging device to expose an adhesive; and applying the adhesive to the patient to secure the bridging device to the patient.
 7. The method of claim 5, further comprising attaching a lower surface opening of a second bridging conduit to an upper surface opening of the pre-attached bridging conduit.
 8. A tissue treatment device, comprising: an elongate body with an enlarged proximal end and a distal end smaller than the enlarged proximal end, and a cavity therebetween; an elongate support structure located in the cavity and configured to facilitate a transmission of reduced pressure along the elongate body; a tubing connector attached to the enlarged proximal end of the elongate body and in communication with a proximal opening of the elongate body; and a wound cover attached to the distal end of the elongate body and in communication with a distal opening of the elongate body, the wound cover comprising a non-rectangular, non-square, non-circular, non-oval shape.
 9. The tissue treatment device of claim 8, wherein the distal opening of the elongate body has a surface area of at least 1 square cm and through which at least 1 square cm surface area of the elongate support structure is exposed.
 10. The tissue treatment device of claim 8, wherein the wound cover has a bi-lobed configuration.
 11. The tissue treatment device of claim 8, wherein the wound cover comprises an open proximal end and a closed distal end.
 12. The tissue treatment device of claim 11, wherein the wound cover further comprises a tab extending proximally from an edge of the open proximal end.
 13. The tissue treatment device of claim 11, wherein the wound cover further comprises a cavity with a longitudinal axis between the open proximal end and the closed distal end, the cavity comprising a diameter transverse to the longitudinal axis that is less than 4 cm.
 14. The tissue treatment device of claim 13, wherein the diameter transverse to the longitudinal axis that is less than 3 cm.
 15. The tissue treatment device of claim 14, wherein the diameter transverse to the longitudinal axis that is less than 2.5 cm.
 16. The tissue treatment device of claim 8, wherein the elongate support structure comprises an open-cell foam.
 17. The tissue treatment device of claim 8, wherein the elongate support structure protrudes through the distal opening.
 18. A low-profile device for delivering reduced pressure to a load-bearing wound site, comprising: a distal port configured to connect to a wound dressing positioned over the load-bearing wound site; a proximal port located a distance from the distal port and configured to connect to a reduced pressure source; a conduit body comprising an inner channel extending between the distal port and the proximal port, wherein the inner channel has a non-circular profile having a width larger than a height of the conduit body; and a plurality of support structures protruding into the inner channel, wherein the plurality of support structures have a porosity sufficient to allow a delivery of reduced pressure to the load-bearing wound site and a flow of fluid from the load-bearing wound site through the inner channel.
 19. The device of claim 18, further comprising a sealing layer comprising an adhesive lower surface configured to be adhered to the load-bearing wound site.
 20. The device of claim 19, wherein the adhesive lower surface comprises a material that absorbs moisture and maintains skin health.
 21. The device of claim 20, wherein the conduit body comprises an adhesive lower surface configured to prevent movement of the conduit body relative to an underlying skin surface.
 22. The device of claim 21, wherein a junction between the adhesive lower surface of the conduit body and the adhesive lower surface of the sealing layer comprises an interruption to prevent peel propagation of the conduit body to the sealing layer.
 23. The device of claim 19, wherein a distal region of the conduit body surrounding the distal port is coupled to an upper surface of the sealing layer.
 24. The device of claim 23, wherein the distal region of the conduit body is permanently coupled to the upper surface.
 25. The device of claim 18, wherein the plurality of support structures comprise a plurality of individual elements positioned within the inner channel and configured to mitigate collapse of the inner channel upon application of external pressure to the conduit body.
 26. The device of claim 18, wherein the plurality of support structures comprise elongate ribs coupled to an inner wall of the conduit body.
 27. The device of claim 18, wherein the plurality of support structures are sandwiched between an upper cover and a lower base of the conduit body.
 28. The device of claim 18, wherein at least one of the plurality of support structures are selected from the group consisting of a mesh structure, a synthetic textile, foam, fabric, non- woven fabric, silicone, urethane, cotton and gauze.
 29. The device of claim 18, wherein the conduit body has a first durometer and the plurality of support structures have a second durometer.
 30. The device of claim 29, wherein the first durometer is less than the second durometer.
 31. The device of claim 29, wherein the first durometer is more than the second durometer.
 32. The device of claim 18, wherein the plurality of support structures are arranged adjacent to the distal port to evenly distribute loads and maintain patency of the distal port upon application of external pressure to the distal port.
 33. The device of claim 18, wherein when the distal port is applied to the wound dressing positioned over the load-bearing wound site, the proximal port is configured to be positioned at a non-load bearing location remote from the wound dressing, and wherein the distance of the proximal port from the distal port ranges from about 2 inches to about 12 inches.
 34. The device of claim 18, further comprising a pressure indicator configured to indicate pressure delivered locally to the load-bearing wound site.
 35. The device of claim 18, further comprising a contact surface positioned under the conduit body.
 36. The device of claim 18, further comprising a padding material located on an exterior surface of the conduit body.
 37. The device of claim 36, further comprising: a low-tack adhesive located on at least a portion of the padding material and configured to adhere to a patient's skin; and a release liner releasably adhered to the low-tack adhesive, wherein the release liner comprises a porous or padded material configured to contact the patient's skin. 